The present invention relates to box type game calls which are utilized by hunters and others to attract wild turkeys and other birds toward the user.
Open boxes in which the tops of a pair of elongated side walls are scraped by a loosely hinged cover to make bird-like sounds have been used for many years. One of the first U.S. patents for such a device was issued Jan. 5, 1897, to Gibson (U.S. Pat. No. 574,534). Gibson recognized that the combination of an upwardly open box with elongated wooden sidewalls and a cover with a transversely curved bottom surface which is loosely hung at one end of the box can be employed to make a turkey-like sound by scraping the cover across the top edges of the sidewalls. The sound produced by Gibson's device lacked the quality to fool many tom turkeys, however, Fleener (U.S. Pat. No. 2,511,403) modified Gibson's invention by tapering the sidewalls longitudinally and tilting them inward slightly. Unfortunately, this modification yielded a noise that is similar to the call produced vocally by a goose and was of little use to turkey hunters.
Subsequent attempts to achieve realistic sounds in game calls were made by Lee in U.S. Pat. No. 4,343,108 and by Moss in U.S. Pat. No. 4,422,262. Lee offered a combination having an upwardly open, elongated wooden box and an actuator top attached thereto in which the box is divided longitudinally into two laterally opposed sound chambers by a common sidewall or sound board. The presence of a third sidewall in Lee's call allows one to vary the sounds which can be generated with it by repositioning a screw about which the actuator top is pivoted; the pivot determines which of the three sidewalls is struck as the actuator top is being moved across the open box.
Moss'device is similar to Lee's, but the common sidewall has a greater span vertically than the two outer sidewalls and is tilted relative to them. When the third sidewall is set in motion by the actuator top, a sound of a different pitch is made when the remaining two sidewalls are struck.
Nevertheless, each of the game calls in the cited prior art is only capable of making sounds which are analogous to those made by the vocal chords. The inventors of these calls failed to realize that distinctive voice sounds are made not only by the vocal chords but also are the products of resonance chambers such as are typically found within the nose and throat of vocal creatures. Specifically, the improvements made by Lee and by Moss in adding a third sidewall or sound board were comparable to increasing the number of vocal chords. The need to give a game call a more realistic sound by providing a resonance chamber which is distinct from the sound box containing the sound boards was not recognized, and hence resonance for a wide range of tones which is required to approximate closely the actual sounds made by a turkey was not possible. As a consequence, the turkey calls in the prior art, although workable, failed to bring in many of the birds that would have been attracted if the sound had been closer to that made by the game itself.